Past and present changes of the Antarctic ice sheet:
Satellite observations of the Antarctic ice sheets reveal a heterogeneous view of change which, however, is increasingly fitting into an overall consistent picture. As shown by progressively longer time series the West Antarctic Ice Sheet (WAIS) is gradually losing mass by dynamic thinning initiated by subglacial melt near the ice shelf grounding zone.
The negative mass balance of WAIS, the primary cause of Antarctica’s contribution to global sea level rise, is only partly compensated by increased snow fall and a slightly positive mass balance of the East Antarctic Ice Sheet. Individual outlet glaciers of the former Larsen B ice shelf have stabilized after a period of post-collapse retreat, a process which is not expected for a marine ice sheet like WAIS.
Partly as a result of surface melt, but primarily because of oceanic forcing, the increased thinning of ice shelves around the Antarctic Peninsula, the Bellingshausen and Amundsen Sea suggest a continued retreat and disintegration of ice shelves and subsequent destabilization of grounded ice in the near future.
Advancement in technology and analysis techniques will contribute to the improved understanding of the observed changes building a basis for better forecasts of ice sheet decay and sea level rise expected over the next few decades.